Glutathione disulfide

Glutathione disulfide

Glutathione disulfide (GSSG) is a disulfide derived from two glutathione molecules. In biological systems, glutathione disulfide is a sign of oxidative stress and is reduced back to glutathione by the enzyme glutathione reductase.

Structure and properties

Glutathione disulfide is a linear dipeptide, composed of two glutathione molecules linked by a disulfide bond. The disulfide bond is formed between the sulfur atoms of the cysteine residues of the two glutathione molecules.

Biological role

In cells, glutathione disulfide is formed as a result of the oxidation of the thiol group of glutathione. This oxidation is a sign of oxidative stress in the cell. The formation of glutathione disulfide is reversible, and it can be reduced back to glutathione by the enzyme glutathione reductase. This reduction is an important part of the cellular defense against oxidative stress.

Clinical significance

Elevated levels of glutathione disulfide in cells can be a sign of oxidative stress, which can be caused by a variety of factors, including exposure to toxins, radiation, and certain diseases. As such, the ratio of glutathione to glutathione disulfide in cells is often used as a marker of oxidative stress.

See also

• Glutathione
• Oxidative stress
• Glutathione reductase